One of the first steps of making any prototype is to design it. Fortunately, the heavy lifting has already been done here...
The link below allows you to access all of the 3D models needed for this project.
The .STL files in the Box folder should be compatible with any 3D printer. If you have a MakerBot Replicator+, you can simply use the .PRINT file to produce all of the generator components on one build plate.
There are only 7 essential 3D printed components. You can either print them all at once, or you can do each .STL component as a separate print job.
Before this research project, I had ZERO experience with 3D design, computer aided design (CAD), or digital modeling.
Through a free personal license of Autodesk's Fusion 360 CAD software, I taught myself enough basic skills to design a printable electric generator casing.
Use the link below to obtain a free version of Autodesk Fusion 360, and you can begin to teach yourself 3D design.